A short walk from Erdene Zuu stands a large carved phallic rock, one of the more unexpected sights on the Mongolian steppe. Local tradition holds that it was placed here deliberately as a reminder to the monastery's monks of what they had renounced — a carved object of temptation positioned within sight of their vows. Whether or not that explanation is entirely true, it is the one every guide tells, and it has the satisfying quality of being just plausible enough to be taken seriously.
The rock is easy to find and takes only a few minutes to visit, but it draws a disproportionate number of photographs. It says something about the Mongolian sense of humour — and perhaps about the relationship between Buddhism and the older animist traditions it layered over — that this object has survived intact for centuries. Worth a short detour if you are already walking the monastery grounds.